The last few decades have witnessed a particularly rapid rise in weight and obesity for individuals of all ages. While weight growth in children and working-aged adults has received the most attention, the public health consequences of excess weight for the near-elderly and elderly are considerable. This research will identify the determinants of weight gain in these older populations, and the consequences for health. To guide the research, we will develop a dynamic economic model of weight gain that illustrates the relationships between food prices, exercise availability, income, and weight. The empirical investigation will begin with some descriptive analysis designed to characterize the changing age-profile of weight and weight gain, by socioeconomic status and other demographic characteristics. We then turn to two important economic determinants of weight: food prices and retirement. Previous studies have demonstrated a link between food prices and weight, but the relationship for the elderly is not known, nor is the effect of retirement. We present preliminary evidence that retirement has substantial effects on weight, and that these effects vary with occupational characteristics in theoretically predictable ways. Next, we examine the complex relationships between weight and health. We first propose to study the effect of food pricing and availability on nutritional status, using objectively measured data on blood nutrient levels. This provides insight into the way in which food intake, if properly targeted, can improve health. This leads naturally into an investigation of the causal impact of weight on health. We will use variation in weight generated by food price variation and state-level exemptions of food from sales taxes. We will explore the effect of this variation in weight on health. Finally, we propose policy analyses based on our work. We will investigate the effect of hypothetical food taxation policies on weight, health, and nutrition. [unreadable] [unreadable]